Thermoelectric refrigerating apparatus



THERMOELECTRIC REFRIGERATING APPARATUS Robert L. Eichhorn, Benton Harbor, Mich., assignor to Whirlpool Corporation, a corporation of Delaware Filed Apr. 25, 1958, Ser. No. 730,908 i 2 Claims. (Cl. 62'-3) This invention relates to a refrigerating apparatus and in particular to means for removing condensate in a refrigerating apparatus.

A principal feature of the invention is the provision of a new and improved refrigerating means utilizing Peltier Effect thermoelectric heat transfer means.

Another feature of the invention is the provision of such a refrigerating means arranged to collect and utilize the condensate from within the refrigerated enclosure to remove heat from the hot junction of the heat transfer means, providing improved efliciency of operation.

A further feature is the provision of such a refrigerating means wherein the collected condensate is caused to be evaporated as a result of a heat transfer from the hot junction, thereby eliminating the need for an outside drain.

Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawings, wherein:

Fig. 1 is a view partially in front elevation and partially in vertical section, of a refrigerating means embodying the invention;

Fig. 2 is a transverse section thereof taken approximately along the line 22 of Fig. 1; and

Fig. 3 is an enlarged fragmentary view of the heat transferring means, electrical circuit means associated therewith being shown schematically.

In the exemplary embodiment of the invention as disclosed in the drawings, a refrigerator 10 comprises an insulating enclosure 11 having a bottom wall 12 and a removable front door 13 providing access to an interior space 14 within the enclosure.

Means for refrigerating space 14 comprises a plurality of thermoelectric elements 15 which function on the Peltier Effect principle to absorb heat at a cold junction 16 and dissipate heat at a hot junction 17 as the result of a direct current flow therebetween through an interposed element 18. For a complete disclosure of the structure and functioning of such thermoelectric means, reference may be had to the co-pending application of Mervin K. Baer and Charles R. Lopp, Serial No. 735,804, filed May 16, 1958.

As best seen in Figs. 1 and 2, the upper surface 19 of bottom wall 12 is sloped downwardly toward the center of the enclosure. Extending downwardly from the central, lowermost portion of surface 19 is a drain tube 20 which extends through bottom wall 12 into a chamber 21 below enclosure 11. A trough 22 is disposed within chamber 21 to collect condensate delivered from refrigerator space 14 through drain tube 20.

As alluded to briefly above, thermoelectric means 15 extend through bottom wall 12 of the enclosure. As best seen in Fig. 2, cold junctions 16 extend in the horizontal plane of the upper outer edge 23 of bottom wall surface 19. Overlying cold junctions 16 is a perforate protective plate 24. Plate 24 is preferably formed of a heat conducting material permitting ready heat transfer therethrough from space 14 to the cold junctions 16. To pre- "ice clude an electrical short between the cold junctions through plate 24, either or both of the cold junctions and the plate may be provided with an insulating surface therebetween such as by anodizing or lacquering. To preclude shorting between elements 18 or hot junctions 17 by condensate on surface 19 draining through tube 20, the

elements 18 and hot junctions 17 similarly may beinsulatingly coated.

tween the fins through the condensate 27, the fins may be insulatingly coated as by anodizing or lacquering. As best seen in Fig. 1, the fins 25 are arranged in parallel spaced planes facilitating the air flow therebetween.

By submerging ends 26 of the fins within the body of collected condensate, two desirable results are obtained. Firstly, the collected condensate, being relatively cool, absorbs heat from fins. 25 thereby removing the heat from the hot junctions 17 and improving the efiiciency of the thermoelectric means. Secondly, the transferred heat energy causes improved evaporation of the collected condensate so that the condensate may be removed by evaporation into the surrounding atmosphere eliminating the need for a drain from the refrigerator 10. To facilitate this evaporation, fan means 28 may be provided within chamber 21 for moving atmospheric air more rapidly through the chamber. In addition to improving the rate of evaporation, the fan means 28 effects improved heat transfer directly from the fins 25 to the surrounding air.

As shown in Fig. 3, the electrical energization of the thermoelectric means 15 is effected through a first direct current lead 29 connected to a terminal 30 electrically associated with the hot junction 17 of one thermoelectric means 15. The opposite polarity lead 31 is connected to a terminal 32 electricallyassociated with the hot junction of another one of the thermoelectric means 15. Between terminals 30 and 32, the thermoelectric means are arranged in a series circuit with the cold junctions 16 and the hot junctions 17 electrically connecting alternatively successive elements 18. Where the available power supply is alternating current, a rectifier 33 may be provided to supply the necessary direct current to terminals 30 and 32. As the thermoelectric means 15 function oppositely upon a reversal of the direction of current flow therethrough, it is a simple matter to effect a defrosting operation in refrigerator 10 by reversing the polarity of the potential applied to the terminals 30 and 32. This causes junction 16 to become the hot junction and junction 17 to become the cold junction whereby space 14 is warmed rather than cooled, as desired.

Thus, refrigerator 10 is arranged to provide an automatic removal of condensate from space 14. Such condensate passes through perforate plate 24 to drop onto surface 19. The sloped arrangement of surface 19 causes the condensate to run to the center thereof where it is delivered through drain tube 20 to trough 22. The body 27 of collected condensate in trough 22 improves the efficiency of thethermoelectric means 15 by withdrawing heat energy from fins 25 whereupon the condensate is evaporated and discharged from the refrigerator to the surrounding atmosphere.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the con struction and arrangement may be made without depart ing fromthe spirit and scope of the invention'as defined in the appended claims.

I claim:

1. Refrigerating means, comprising: an enclosure; thermoelectric means having a plurality of cold junctions in'heat absorbing relationship-with the interior of the enclosureand a plurality of hot junctions exteriorly of the enclosure; a plurality of heat dissipating fins associated with the hot junctions for conducting heat therefrom; a container into which the fins extend; means for conveying condensate 'from said enclosure to said container for cooling said fins; and means for forcing a stream of cooling air in thermal transfer association with 4 said fins and the condensate in the container, the'fins being arrangededgewaysto said stream of cooling air.

2. The refrigerating means of claim 1 in which said fins are arranged in a plurality of substantially parallel rows.

References Cited in the file of this patent UNITED STATES PATENTS 413,136 Dewey Oct. 15, 1889 2,029,860 Daernicke Feb. 4, 1936 2,250,612 Tanner July 29, 1941 2,732,689 Shreve, Jan. 31, 1956 2,779,172 Lindenblad Jan. 29, 1957 

